<template>
  <div id="home">
    <nav-bar class="home-nav"><div slot="center">购物街</div></nav-bar>
    <tab-control
        :titles="['流行', '新款', '精选']"
        @tabClick="tabClick"
        ref="tabControl1"
        class="tab-control" v-show="isTabFixed"/>
    <scroll
      class="content"
      ref="scroll"
      :probe-type="3"
      @scroll="contentScroll"
      :pull-up-load="true"
      @pullingUp="loadMore"
    >
      <home-swiper :banners="banners" @swiperImageLoad="swiperImageLoad"/>
      <recommend-view :recommends="recommends" />
      <feature-view />
      <tab-control
        :titles="['流行', '新款', '精选']"
        @tabClick="tabClick"
        ref="tabControl2"
        />
      <goods-list :goods="showGoods" />
    </scroll>

    <back-top @click.native="backClick" v-show="isShowBackTop" />
  </div>
</template>

<script>
import HomeSwiper from "./childComps/HomeSwiper";
import RecommendView from "./childComps/RecommendView";
import FeatureView from "./childComps/FeatureView";

import NavBar from "components/common/navbar/NavBar";
import TabControl from "components/content/tabControl/TabControl";
import GoodsList from "components/content/goods/GoodsList";
import Scroll from "components/common/scroll/Scroll";
import BackTop from "components/content/backTop/BackTop";

import { getHomeMultidata, getHomeGoods } from "network/home";
import {debounce} from 'common/utils'

export default {
  name: "Home",
  components: {
    NavBar,
    HomeSwiper,
    RecommendView,
    FeatureView,
    TabControl,
    GoodsList,
    Scroll,
    BackTop,
  },
  data() {
    return {
      banners: [],
      recommends: [],
      goods: {
        pop: { page: 0, list: [] },
        new: { page: 0, list: [] },
        sell: { page: 0, list: [] },
      },
      currentType: "pop",
      isShowBackTop: false,
      tabOffsetTop: 0,
      isTabFixed: false
    }
  },
  computed: {
    showGoods() {
      return this.goods[this.currentType].list;
    },
  },
  deactivated() {
    this.$bus.$off('itemImageLoad')
  },
  created() {
    // 1.请求多个数据
    this.getHomeMultidata();

    //  2.请求商品数据
    this.getHomeGoods("pop");
    this.getHomeGoods("new");
    this.getHomeGoods("sell");
  },
  mounted() {
    // 1.图片加载完成的事件监听
    const refresh = debounce(this.$refs.scroll.refresh,50)
    this.$bus.$on('itemImageLoad', () => {
      refresh()
    })
   
  },
  methods: {
    // 事件监听相关方法
    tabClick(index) {
      switch (index) {
        case 0:
          this.currentType = "pop";
          break;
        case 1:
          this.currentType = "new";
          break;
        case 2:
          this.currentType = "sell";
          break;
      }
      this.$refs.tabControl1.currentIndex = index;
      this.$refs.tabControl2.currentIndex = index;
    },
    backClick() {
      this.$refs.scroll.scrollTo(0, 0);
    },
    contentScroll(position) {
      // 1.判断BackTop是否显示
      this.isShowBackTop = (-position.y) > 1000;

      // 2.决定tabControl是否吸顶 fixed
      this.isTabFixed = (-position.y) > this.tabOffsetTop
    },
    loadMore() {
      this.getHomeGoods(this.currentType);
    },
    swiperImageLoad() {
      this.tabOffsetTop = this.$refs.tabControl2.$el.offsetTop;
    },

    //网络请求方法
    getHomeMultidata() {
      getHomeMultidata().then((res) => {
        this.banners = res.data.banner.list;
        this.recommends = res.data.recommend.list;
      });
    },
    getHomeGoods(type) {
      const page = this.goods[type].page + 1;
      getHomeGoods(type, page).then((res) => {
        // console.log(res);
        this.goods[type].list.push(...res.data.list);
        this.goods[type].page += 1;

        // 完成上拉加载更多
        this.$refs.scroll.finishPullUp();
      });
    },
  },
};
</script>

<style scoped>
#home {
  /* padding-top: 44px; */
  height: 100vh;
  position: relative;
}
.home-nav {
  background-color: var(--color-tint);
  color: #fff;
  /* position: fixed;
  left: 0;
  right: 0;
  top: 0;
  z-index: 9; */
}
.tab-control {
  position: relative;
  z-index: 9;
}

.content {
  overflow: hidden;
  position: absolute;
  top: 44px;
  bottom: 49px;
  left: 0;
  right: 0;
}

</style>
